I'm confident that BYU is an excellent academic institution, I would expect a better understanding of the most basic principles of economics here.
Utah has sold out for more the last decade, and there are way more people that want to go than can go. Therefore prices go up.
Lets take the Holy War as an example. You see Rice-Eccles holds about 52k people. When only, say, 36k people want tickets, the price goes down. But when, say, 100k people want tickets, there is more demand than there is supply and therefore the prices go up.
There are well more than 100k people who would love to go to the first Holy War in 3 years, the first in conference match up since 2010, the fact that Utah is both expected to have a very strong team and Utah lost to BYU last time and demand from Utah fans is at an all time high.
Do you really expect Baylor to get up for a game against BYU as much as Utah fans would? Do you honestly think that a Holy War at Lavell Edward's Stadium wouldn't cost substantially more than a game against Houston?
Economics 101.